Note, the Omega theme (in its Alpha base theme) also has an interesting way to remove core CSS files. It does this by specifying excluded CSS files in the .info file and then using some functions -alpha_settings() and then (same as Tao) hook_css_alter() - to unset the specified css.

The Tao approach is much much simpler in terms of code. But Omega is nice too because it is very friendly to non-developers (just add exclude[] to your info to remove a CSS file).